Electromagnetically driven valves have a magnet coil, a magnet armature for opening and closing the valve, and a magnet housing. In the case of simple designs, the magnet housing is made up of a solid sheet metal part bent into a U-shape. These designs are preferably suitable for a direct current control. In the case of an alternating current control, these designs produce heavy eddy current losses. Bearing in mind the permissible heating, a lower amount of effective power and, hence, less magnetic force is thus available. In addition, it is known from the generic document DE 198 60 631 A1, for example, to produce the magnet housing in one piece from a sheet metal strip which is first punched out and subsequently rolled or bent. There are, however, only limited possibilities of shaping here.
Other alternating current operated solenoid valves are provided with magnet housings made of sintered ferrite material to avoid eddy currents. While these housings are also suitable for direct voltage operation, two valve configurations are fabricated for reasons of cost-saving. In contrast to an alternating current operated valve, no expensive special material such as sintered ferrite is used for the magnet housing of a direct current operated valve, but reasonably priced sheet steel.